Additive Manufacturing (AM) has been hailed as the “third industrial revolution” by Economist magazine (April 2012). Additive Manufacturing (AM) builds up a material to suit the service performance in a layer by layer or even pixel by pixel with appropriate materials to match the performance, which will enhance the productivity and thus reduce energy consumption. Flexibility and capability of producing near net shape critical components directly from Computer Aided Design (CAD) is partly responsible for its attraction.
There is wide spectrum of processes under the umbrella of Additive manufacturing. For metallic components two main types are: Powder bed based processes such as Selective Laser Sintering (SLS) and pneumatically delivered powder based processes such as Direct Metal Deposition (DMD). Both processes have their relative strength and weaknesses. One common problem is that postmortem quality assurance is not adequate. However, on line diagnostics and process control has the tremendous potential to reduce waste, cost and conserve energy. This offers a unique opportunity to take corrective action during AM—layer by layer, if not pixel by pixel.